Support muting specific calendars

Is your feature request related to a problem? Please describe.

Users in our organization often have multiple calendars:

• Some personal
• Some for small groups/teams
• Some which are available to all users in our organization

Because of the character of the global calendars (e.g. Meeting Room bookings) they might want to not receive notifications for all new events added to those calendars - but when disabling notifications for calendar events they won't receive notifications for the other calendars (e.g. Team Schedule).

Describe the solution you'd like

I would propose adding a "Mute Calendar" feature, to each calendar:

This should be possible to enable per user, but also as a default by the owner of the calendar:

Describe alternatives you've considered

Muting all calendars is what we do right now. But this leads to people to be unable to use the useful feature of activity notifications

Additional context

No response

Start by reviewing the existing calendar notification settings and the per-calendar controls shown in the issue screenshots. Trace how muting all calendars currently works, then define how per-user muting and an owner-provided default would behave; done means notifications can be muted for one calendar without disabling them for others.